One shot of Eren x Male Reader. Let's see what Mikasa has to say.

"Eren".

Everyone in the room except Mikasa, Jean and Eren smiled. Even the person who talked smiled, although it was more a gesture of resignation. They all knew that Eren and (y/n) didn't connect very well. The older recruit was one of Jean's closest friends (even closer than Marco), with whom he shared an acid sense of humor and sharp wits (and comments). At the same time, he and Jaeger had a tacit arrangement of sorts, a strong rivalry not usually shown physically through fighting and arguing, but in the way they competed each other every time they met, on every ocassion and training, be it 3DMG, hand-to-hand combat, pretty much anything was an excuse to push each other to the limit. (y/n) was in advantage since he was physically stronger, yet Eren's iron will had given him some spectacular victories from time to time. They apparently hated each other... and also admired each other, secretly.

And now, on this holiday in the training camp, they were about to spend seven minutes in heaven. They headed to the closet.

"Try not to be too passionate guys" Connie said laughing. Both guys flipped the bird.

Once the door closed, Eren stood on the wall in front of (y/n), arms firmly crossed.

"So, anything we can do to make time go faster?" He said with a bored look on his face. "After all, this stupid game wasn't my idea." As his game partner didn't answer, he looked at him "What's wrong now? Are you ignoring me?"

"... Wanna make out?"

In the seconds of complete, absolute silence that followed the sentence, Eren swore he could hear his heart beating. He blinked in confussion, thinking this was nothing but a clumsy attempt to joke. "Dude, if you're going to joke, at least use a better tone. That sounded serious."

"I am serious" (y/n) answered softly. "I want to make out with you." His (e/c) eyes stared into Eren's pupils, making him nervous. "Really."

"Wh-what are you... why?"

"Because you're kind of... cute, Eren" He never called him Eren. He always called him by his surname, or any nickname (usually "Ragemonger" or "Avenjaeger") when they were competing. "And strong. Very strong. I like that. Don't you?"

"Well, you flatter me." Eren felt his cheeks blushing, and thanked that the light was dim "But i'm not into guys, so..."

"You don't seem very interested in girls, come to think of it. You always avoid the subject."

"That's because they are... complicated."

"Whimsical."

"Sudden changes of humor."

"Use of an unknown language, yeah, i don't get them either. What i mean is, are you not into guys, or are you afraid you like it?"

Eren opened his mouth to reply, but nothing came to his lips. True, he never thought of any girl in the camp as a possible girlfriend. He never told anyone, but he was... afraid of them. He had seen how possesive they could be, how smothering, with Mikasa taking him away from every quarrel (sometimes literally). He suddenly thought of all the times he and (y/n) had battled in the training grounds. How they sometimes fell on each other, exhausted and sweating, dragging themselves back to the barracks or even the showers, how they struggled to be better, faster, stronger. How there were ocassions in which they would stop on their way back to talk about their performance, pointing at each other weaknesses and strengths. It was because of this guy -this calculating, skillful, and sometimes asshole of a roomate- that he had improved. And he knew it, by the way he was looking at Eren's face with badly disimulated desire. Eren's heart started beating faster. Before he realized, he gave a step towards (y/n). Grinning, the other did the same. When they met, (y/n) arms surronded Eren's hips while the younger recruit put his arms around his neck, eyes closed, lips slighlty open. WIth a tender smile, (y/n) kissed Eren softly, feeling his back and butt playfully with his hands. They separated, Eren's eyes showing a mixture of desire and shame. (y/n) smiled, tracing Eren's lips with a finger, making him shiver.

"Do you want more, Jaeger?" He said teasingly "Do you want another kiss?" The other nodded anxiously "Even if it is a bit... dirty?"

He leaned and planted a kiss on his lips. Eren felt his tongue playing, prying his teeth to get into his mouth. He felt his hand going under his shirt, touching his abs, then caressing his hard nipples, finally sliding inside his pants to touch his member. Gasping, Eren broke the kiss, surprised eyes staring at (y/n), who then proceeded to feel him with his hand, manipulating his genitals to make him moan louder, giving a playful bite on his ear. Eren's body was burning when he was pushed against the wall, pants and trunks down, shivering when his roommate inserted a finger in his ass, unable to control himself when he grabbed his member and began penetrating him. Eren bit his lower lip, holding a loud moan as he heard the grunts coming from behind as (y/n) assaulted his virgin cavity. "Not so virgin now" was Eren's last lucid thought before being overwhelmed by the sensation of being fucked raw against the wall, his lover against him, thrusting fast and hard, pulling only a few inches out, like a dog in heat, masturbating him with his free hand.

Everyone in the room was breathing heavily. Nobody knew when they were supposed to open the door. Their eyes were fixed on the closet. When the sounds started, they chuckled, surely (y/n) and Eren decided to play along, making lewd noises to fool around. Until Sasha went and opened the door. Before anyone could see anything, she closed the door quickly, face as red as a tomato, eyes wide as a full moon, and sat back on her place. Nobody understood, and Mikasa became worried.

"Sasha, why did you close the door? Did something bad happen?" -Strong head shaking- "Did something happen to Eren?" Strong nodding. "What? What is it?" Sasha opened her mouth, sweating, but before she colud talk, a loud moan, followed by short grunts, came from the closet, startling everyone. Then another moan. It sounded like Eren, but... Jean suddenly said "Are those two... fucking?!" Sasha closed her eyes and nodded then let out a sigh and covered her ears, as the sounds began to increase their volume. More moaning, and slamming noises came from inside. Finally, two simultaneous screams of pleasure were heard, and then silence, broken from time to time by a soft panting.

The door opened and everyone looked. Eren and (y/n) came out shyly, both blushing, the latter with a slight smile. They were holding their hands. Instead of sitting, they stood a few feet away from the rest, and finally (y/n) spoke.

"You may want to try another game, guys. Seriously, you don't want to to enter there now." he said, chuckling. He pulled Eren to a nearby chair, and then made him sit on his lap, gently hugging him. The younger boy smiled cutely, closing his eyes and laying against him, letting his soft touch lull him into a faint sleeping.

After that, the rest tried another games, while taking a look at them from time to time. Only Jean and Mikasa didn't participate, both a bit disturbed by the sudden change in their friends. (y/n) and Eren were the impersonation of tenderness, both in their own world. A while later, (y/n) whispered something into his new boyfriend's ear. Eren nodded, and then the older recruit stood up, lifting him in his strong arms, taking him to the outside into the cool night. Mikasa followed them to the door, watching as they left. Unlike the times she carried Eren away from trouble, he was smiling, hugging to the other male. She wiped a tear from his cheek and headed inside, where Jean offered her a drink, muttering something about "didn't see that coming either."

The morning after

Eren and (y/n) appeared in the barracks as the rest of their roommates were preparing. They had spent the whole night outside, playing with each others body in the lake's border near the forest. Eren eyes had a sparkle that didn't disappear even when (y/n) asked him to leave him alone with Jean a few minutes. Blowing a kiss, Eren went with his comrades, who received him warmly, without any kind of comments about the past night's events.

"Jean" said (y/n) "Are you mad?" His friend looked at him, sizing him up.

"No... well, sort of. I never knew you where into guys. Not that i mind. But, did you have to pick that guy? I mean, come on, you know him!"

"Indeed. It is because i know him that i chose him. Actually, i should thank you." The other eyed him curiously.

"Why?"

"Because if we weren't friends, i would have never realized how much i liked Eren. Remember our chat, when i told i would find a way to help you with Mikasa? My competition with Eren was born from that. I wanted to get to know him, become his friend, so i could maybe get you closer to her." Kirstein's eyes grew wide. "You know, a friend's favor. But... i got to see much of him. His passion, his strength, his commitment. I'm going to the Corps with him, Jean. We decided it last night. Sorry it didn't turn out as planned. We still friends?" he finished, looking at Jean apologetically.

He frowned, opened his mouth, closed it, and finally lifted his hands, resigned. "Whatever man. You were always a twisted turd" he smiled a bit "But thanks for the effort. I hope you guys are happy. Maybe some good fucking like last night's will keep him from shouting at me."

Later, as Jean was heading for hand-to-hand combat training, he felt a hand on his shoulder. It was Mikasa.

"M-Mikasa! Hey, how are you?"

"... Fine, thanks. Jean, the instructor told me to train with you today. He said you were really making progress in this training, and wanted me to test you."

"Oh, yes! I mean, great, let's do this."

"Jean?" Mikasa's unsure tone surprised him.

"What's wrong, Mikasa?"

"Do you think Eren is happy with your friend?"

He looked at her. Her eyes were a bit teary, but at the same time, it was as if she was expecting him to tell her so. He blinked, confused.

"Well, judging by Eren's face when they appeared this morning, he is."

"This morning?" Mikasa frowned.

"Yeah" Jean shrugged "It seems they spent the whole night outside, you know... doing... that."

Mikasa closed her eyes. Instinctively, Jean placed his hands on her shoulders reassuringly, without realizing what he was doing. To his surprise, she smiled warmly.

"Thanks, Jean. I needed to know. I... i alwasy fantasized of having a life with Eren, but now i know it was nothing but a foolish dream... i'm satisfied with him being happy, even if not with me... i guess my fate is to be alone."

"Mikasa, stop!" Jean's strong tone startled her "Look, i know you had feelings for him, ok? I was jealous, very jealous. But i won't stand watching how you abandon yourself to loneliness. You are the strongest, smartest, most beautiful girl i've ever..."

When Mikasa threw herself on him, grabbing him by his jacket and pulling him into a kiss, Jean's world froze. Never, even in his wildest dreams, he had hoped to see her so passional, as she put her arms around his neck, holding him against her, as he finally managed to make his brain work and hugged her waist, lifting her a bit. When they finally broke the kiss, she looked at him, blushing.

"Do you really think that way of me?" her eyes full of gratefullness, and a bit of shame.

"Since the first moment i saw you, Mikasa" he said, smiling, as he caressed her face gently.

"It's strange. Last night, i thought there wouldn't be anyone else for me if it wasn't Eren, but... but knowing he is with someone else, happy and in love, made me open my eyes. My world has widened, thank to him... and your friend"

"A friend's favor" said Jean softly, as they walked towards the camp, hands holding.

There ya go. JeanMika fans, enjoy.